Bag sealing machine



April 27, 1954 R. J. @AUBERT l BAG SEALING MACHINE 5 Sheets-Sheet lFiled Aug. 6, 1951 April 27, 1954 R. J. GAUBERT BAG SEALING MACHINE 5Sheets-Sheet 2 Filed Aug. 6, 1951 INVENTOR. Pe/7e J @abe/ April 27, 1954R. J. GAUBERT BAG SEALING MACHINE Filed Aug. 6, 1951 5 ySheets-Sheet 3INVENTOR. e/ve J cauer/ BY A Il SSII v/Anm ll N\ l April 27, 19544 R. J.GAUBERT BAG sEALING MACHINE 5 Sheets-Sheet 4 Filed Aug. 6, 1951INVENTOR. /Qenc 'auer/ BY MM Hmamwm Imumzwh QQ vfJ//f/f. O j@ April 27,1954 Filed Aug.

R. J. GAUBER-T BAG SEALING MACHINE 5 Sheets-Sheet 5 1N VEN T 0R.

Pene aube r/ Patented Apr. 27, 1954 k'Rene J. Gaubert,

Simplex Pack Oakland, Calif., assigner to ging Machinery, Inc., Oakland,

Calif., a corporation of California Application August, 1951, Serial No.240,569

11 claims.

This invention relates generally toapparatus for performing heat sealingoperations upon'the endsof bags made of materials such as moistureproofcellophane, Pliolm, polyethylene, Saran vinyl base membranesand thelike.

len

In the packaging of the various products in bags made ofthe materialsmentioned above, it has been common practice to apply a heat sealingoperation across the open end o f the bag after the bags have beenfilled. I Manually operated heat sealers have been used for thispurpose, and also machines which perform a heat sealing operationautomatically as the bags traverse through the machine. chines have beensatisfactory for some services', but have not been adaptable to all ofthe various bag materials suitable for heat sealing, as for exampleSaran which is best sealed by the use of electrical means of the highfrequency ca-` pacity type. chines which reliability and struction.

It is an object of the present invention to provide an automatic sealerof the above character which is adapted for use on a wide variety ofbag-making materials, including Saran.

Another object of the invention is to provide a heat sealing machineVwhich is reliable in operation, and which is relativelyl simple in itsconstruction and operating features.

Another object of the an automatic bag sealer control over the heatwhich will avoid the use prior machines.

' Additional objects and features of the invention will appear from thefollowing description 1n vention has been setA tion with theaccompanyin'gvdrawing.

1 Referring'to thedrawing:`

'.Figure lisa plan view'of a machine incorporating the presentinvention.

.FigureZ is a front view of the machine.

. igure 3 is a cross-sectional view on an enlarged scale taken along theline 3 3 of Figure 1. Figure 4 is a cross-sectional view like Figure 3,but with the parts in a diiferent operating position. r'

Figure 5 is an enlarged detail illustrating the belt conveying means inplan, and with certain parts being broken away.

Figure 6 is an enlarged cross-sectional detail illustrating parts, ofthe carriage means for supporting and 4mounting the heating electrodes.

Furthermore, the automatic masimplicity of operation and conwhich willprovide close of heated rollers as in invention is to provide sealingoperation andl which the preferred embodiment of the in` forth in detailin conjunc-v The automatic mahave been available have lacked Fgure '7 isa fragmentary detail shown switch*` operating cam means for thecarriage.

1 Figure 8 is a circuit diagram.

The-machine as illustrated in the drawing consists generally of a framel0 formed by thelongitudinal plates- I |V and |2, and the end connectingmembers port vthe working parts, including the bag conveying means, andthey means for performing the automatic sealing operations.

The bag conveying means is of the endless belt type and consists of twoseries of pulley wheels I4 and I6 that are journaled upon the plates andl2. Endless belts Il and `|8 are tracked upon these pulley wheels, andare preferably of the V type formed of yfabric-reinforced synthetic ornatural rubber. The pulleys 4a and Ilia at one end of the machine arearranged to be driven by suitable means such as an electric motor I9.The drive pulley 2| of this motor is shown connected by belt 22 to thepulley 23 on the shaft of a gear train in casing 26, whereby the twovertical shafts 21 and 28, which carry the pulleys |460 and |6a, aredriven in opposite directions.

at the same speed and The adjacent runs of the two belts l1 and I8 areyieldably pressed tothe tensioning rollers 29.

gether, whereby they will frictionally grip and retain the flattened thebag through the machine.

The outer runs of the belts are engaged by The feed end of the machine(the right hand end viewed in'Figure 1) is provided with guide members30 that arey flared apart to receive a bag between the same. The frameI0 is shown secured to a horizontal- 'E mounting plate 3| that iscarried to vsuitable support means, such as the supporting standard 32.Plate 3| also serves to mount theI electric motor I 9, and theelectronic equipment 33v and i 34 which will presently bev described.

The Vautomatic bag sealing means-is arranged intermediate the ends ofthe frame I0, and func-V tions to periodically grip and operate upon thetops of the bags as the bags are being carried by the conveying belts.Thus intermediate the ends of the frame |0 the plates and |2 serve tosupport the brackets 35 and 3B (Figure 1).

A- pair of horizontal rods -l3'l and 38 are carried' bythese'bracketsrand the rod 38 may extend for attachment to the gearcasing 26 (Figure 2). A carriage designated generally at 39 is slidablycarried by the rod38, and guided by rod 3l. One part of thisv carriageincludes the hubs 4| and 42 (Figure 6) that are secured to the ends of atube 4 3, `and which yare provided` with upl3. This frame serves tosup-g 24. This shaft connects with elementsy top of a bag and thus carrywardly extending lugs 44 and 46. 'I'hese lugs serve to mount the spacedguide rollers 41 and 48 that are positioned in close proximity with theopposite sides of the rod 31.

The tube 43 is shown provided with journals 49 and 50 for slidablyengaging the rod 38. A compression spring is shown engaging the tube 43(Figure 6) in order to urge the entire carriage in one direction.

The hubs 4| and 42 carry arms 52 and 53, the lower ends of which areconnected by the horizontal bar 54 (Figures 3 and 4). This bar in turnserves to carry the mounting member for' the electrode or heating member56.

Between the hubs 4| and 42, there isa' hub 51 which carries thedepending arms 58 and 59.v The lower extremities of these arms areconnected' by the horizontal bar 68 and this bar carries thev mountingmember 6| for the electrode 62 (Figures 3 and 4). 'Ihe hub 51 alsocarries the laterally extending operating arm 63, the free endfof whichis connected by links 64'with the movable member B9 of an operatingsolenoid 61. The solenoid. is carried by themounting plate 69, wh-ichintu-rn is secured toa bar 1| attached to the two lugs 44 and 46. Atension spring 12 is attached to the free end of arm 63, and to a tab 13which is secured to the bar 54. It willy be evident that-whenthesolenoid 61 is energized the arm 63 is moved upwardly as viewedinFigures 3 and 4, and this serves toswing-k the bar 99 and the electrode62 toward the right as Viewed in Figures 3 and 4. When the solenoid isde energizcdthe bar 69 to-A gether with the electrodeA 62 returns to theposition illustrated in Figure 3. uThe limiting position to which theelectrode 62 moves when the solenoid is energized, can be controlled bysuitable means such as the adjustablestop screw 16. This screw iscarriedby a bar 11-, which is attached at its extremities to the lugs 44and 46. The screw 16- engages a lug 18 which iscarried by the hub 51x.

For the heat sealing of bags made of Saran, it is desirable toelectrically connect the electrodes 56' and 62 with the terminals of ahigh frequency generator.

33 and 34 constitutes the equipment for generating the required highfrequency current, and this electronic equipment can be connected to theelectrodes 55 and 52 by suitable flexible conductor leads (not shown).As is well known to those familiar with electronic heating means of thehigh frequency capacity type,fat least one of the electrodes betweenwhich` theY part to be heatedv is placed, is faced with a suitableelectrical insulating (i. e. dielectric) material. In this instance theelectrode- 62V is preferably faced with asuitable dielectric material,such as a sheet or ribbon of synthetic rubber. Electrode may also befaced with suitablefmaterialsuch as cellulose acetate tape. In the eventthe machine is handlingl bags made of moisture-proof cellophane, Pliolm,or like materials,l the electrodes 56 and 62 can consist of electricallyheated metal bars.

The machine is provided with certain electrical switches for securingthe necessary au-v tomatic cycling. Electrical switch is operatedautomatically when aV bag has progressed a cer-4v tain distance throughthe r'nachine.A It-is suitably mounted below` the plate I2 inconjunction with the operating lever 8|'. This lever is fulcrumed at 82,and is arranged with its one end 8|a operating the switch i, and itsother end 8|b provided Awith the bag engaging' member 83. Member' 83extends in proximity with the bag' engag- The electronic equipment ingstrip 84, the latter being a flange formed on the plate 85. Suitablemeans such as the screws or bolts 8B serve to adjustably secure theplate to the plate That end of the strip 84 which is nearest the feedend of the machine is provided with a bevel or inclination 81 forengaging and directing the advancing edges of the bags. A compressionspring 88 urges the lever 8| in a direction to urge the member 83 towardthe strip 84. It may be explained at this point that whenI the advancingedge of a -bag engages the member 83 and the strip 84, the lever 8| ismoved a sufcient amount to operate the switch Another electrical switch2 has an operating member" 9|, which carries a cam roller 92. Roller 92-is engaged by a cam bar 93 mounted upon the' members Stand 59. Oneextremity 94 of this cam bar is inclined downwardly, and the upper faceof the cam bar is provided with a cam button 95 (Figure '1).

Ain additional electrical switch 3 (Figure l) has an'operating roller 95whichis adaptedtobe engaged by plate 91. Plate 91 is mounted upon themembers 58 and- 59, which move when the solenoid is energized. When thesolenoid is deenergized plate 91 is raised with respect to the roller9S, as shown in Figure 3. When the Solenoid 61 is energized however, theplate 91 moves downwardly into horizontal alignment with the roller 96vwhereby when the carriage moves to-v ward the leftasviewed in Figure l,the switch 3` is operated. It may be explained that switch 3 serves tooperate suitable switching means that applies high frequency electricalcurrent to the electrodes 56 and 62.

Plate 91 also forms a part of an interlockf device. Thus when thesolenoid is energized the plate 91' is in such a position that as itmoves to the left as viewed in Figures l and '1, it passes If. thesolenoidv should be beneath the tabY 98x. temporarily deenergized whilethe plate 91 is below the tab 98, then the electrodes will be heldpressed together upon the'bag beingsealed. Plate 91 is shown providedwith oppositely beveled forward and rear edges- 91m and 91h, whichfacilitate movement of the plate relative to the tab 98. The bevelededge 91aY tends to guide the plate belowv the tab 98 for initialmovement ofthe plate 9Vlvto the left as viewed in Figure l, and afterthe plate has cleared the tab 98fand the solenoid has been deenergizedto permit the carriage to return to its initial position, the bevelededge 91h guides the plate 91 over the top of the tab 98.

Figure 8 is asimple circuit' diagram showing the electrical connections.The current supply lines LI andA L2 are shownconnected to the' highfrequencyv equipment 33,' 34 in conjunction with a relay switch 99. Theenergizing circuit |0| for this switch includ'esthe transformer |02` andthe contactso'f the-switch 3^. The energizing cir'- cuit |83 for thesolenoid 61 is connected to the transformer' |02, and isin series iwiththe contacts of switches and 2. The contacts of switchA 2l are normallyclosed, while switch is normally open. When switch is closed solenoid 51is energized, and the solenoid is deenergized when thec'ontac'ts ofswitch 2 are opened. The' electronic equipment is operated to applyl'iigh frequency current to the electrodes 56 and 62, upon closing ofswitch 3.

Operation of my machine can now be explained as follows: Bags are filledmanually or by use of a suitable bag filling machine, and then the upperends ofv the' bags are iiattened. to form a tab. Such a' bag 5' is shownbeing applied in' tendsfdirectly between'the electrodes 56 and 62,5

serve to move the 'bag longietudinally through the'machine. When a baghasl progressed to a position inwhichits tab .6 ex'" its advancing edgeengagesthe member 83 where'-` by the switch is closed. This serves toenergize' the solenoid 61, 62 is immediately inFigure to the baggripping position shown in Figure 4. The upper tab of the bag is nowgripped* between -the electrodes 5.6 and 62, and the gripl issuicieni;whereby as the bag moves forwardly the entire carriage39 moves with thebag'against the compression energizing the solenoid switch 3. so that aspass beneath fthe roller without operating the switch 2. After initialmovement of the carriage 39 takes place, switch 3 y electronic equipment33, 34 supplies high frequency electrical current to the electrodes forthe heat sealing operation.

After a predetermined interval during which time the carriage 39 hasmoved forwardly, the plate 91 clears the roller 96 and the tab .58whereby switch 3 is opened to interrupt further supply of high frequencycurrent. Shortly thereafter lthe cam button 95 engages the roller .92 tooperate the switch 2. Operation of this switch to open its contacts,opens the energizing circuit Also the bar 93 is moved downwardly |03 forthe solenoid 61, and thus the solenoid is" deenergized. When thevsolenoid is deenergized electrode 62 moves back to the positionshownginI to release the grip upon Figure 3, and this serves the bag,whereby the carriage 39 now moves back to the initial position shown inFigure 2, under Also simultaneously;

the'urge of the spring 5|. with deenergizing of the solenoid, plate 91`is moved upwardly to clear the tab 98, and to prevent-operation ofthe-switchj3 as the carriage moves back` to its initial position. Theheat sealed bag'- continues vtoniove through the machine and isdischarged from the left hand end of the machine as viewed in Figure 1.

VItbwill be evident from the foregoing that' I have provided amachinecapable of performing a variety of bag sealingoperations. As previouslymentioned, with material like Saran, it is desirable to make use of highfrequency heat sealing means of the capacity type. With such heatsealing means it is desirable to apply and inter-r rupt the highfrequency electrical current in cone junction with movements of thecarriage 39. in instances where high frequency sealing meansfjyis notemployed, the switch 3 and its operating means can be omitted. Thus inthe heat sealing of bags made of such materials as moisture-proofcellophane. Pliolm, or polyethylene, electrodes 56 and 62 may consist ofmetal bars heatedrby use of conventional electrical heating elements,and the current supplied to these heating elements can be continuous.

I claim:

1. In a machine for heat sealing bags, means for conveying bags along apredetermined path through the machine, with the tops of the bagsextending upwardly and flattened. a pair of heat spring 5L?.Simultaneously with' the'plate 91 is moved into horizontal alignmentwiththe roller 9B of the` it advances toward the roller 92, it willV isoperated whereby the.'

with the result that electrode swung from the position shown V sealingmembers adaptedto clamp the flattened tops ofthe bags between. the sameto perform" heat sealingoperations, a carriage serving to1v mount saidmembers, tracking means for said carriage for movement path parallel tomovement ofthe bags through the machine, means for yieldably urging thecarriage'in a direction the machine to cause said motivemeansto beenergized to thereby'cause the heat sealing memI` bersv to clamp uponlthe 'topofafbag and means carried by the carriage and serving to operatesaid second switch, said second switch whenopf4 erated serving todeenergize said motivemeansj return to said limiting 2. In a machine forheat Asealing bags, means for conveying bags along a predetermined paththrough the machine, ,a pair of heat sealing members adapted to bepositioned in gripping relation with the flattened tops mount saidmembers, one of said membersbeing mounted for pivotal swinging movementwith respect to the other-memben tracking means for along a pathparallel to the riage in a direction opposite movement of the bagsthrough themachine and toward a limiting position of ber toward or awayfrom the to energize same, said solenoid when energized' servingtoucause said heat sealing members to grip the il'attened top of a bagand thereby vcause thecarriagetogether with said members to move-V lalong with the bag for a heat-"sealing operatiom a vrstl switch4included: in said circuit" means for controlling the sameymeansservingto operate said rst switch including a member extending into the path ofmovement of the tops of the bags, said member when moved by engagementwith the top of a bag serving to close its associated switch, a secondnormally closed switch included in said circuit means and serving whenopened to cause said solenoid to be deenergized, means for operatingsaid second named switch including a cam element, said cam element beingmounted to move with swinging movement of said one heat sealing member,said cam element including a portion adapted to actuate said secondnamed switch to open the same after the carriage has moved apredetermined distance to complete a heat sealing operation, said camelement also including a portion serving to retain said second switchactuated during return movement of the carriage to its initial limitingposition.

of the carriage along a' l opposite to the direction 'ofmovement; of the4bags through the machine and.- toward a limiting stop position,electrical motivef' means adapted when energized to cause clampingI ofVsaid heat sealing members across the flat--4 tened end of a vbagwhereby said members toe' gether with the carriage move in synchronis'mwith the bag until' said members are released, electrical circuit meansfor energizing said mol tive means and including a rst and al second-velectrical switch, said rstV switch being disposed to be operated lbymovement-,fof thebags throughA of the bag and to thereby of the bags,one' of said members being movable toward and away from the 'othermember, a carriage serving fto;

the lcarriage meansv including asolenoid lsinfiported vby the carriageand connected'to operate said one sealing meme' other member, electricalcircuit meansl connected to s aid solenoidv aora-444V 31A heatY sealingmachine as in claim 2 in which means is provided forV supplying highfrequency electrical energy to said heat sealing members, and in whichsaid' members are electrodes adapted to causev heat sealingby dielectriclosses.

4; In a machine for heat sealing bags after the insertion of a producttherein, means for conveying separate bags along a predetermined paththrough the machine with the tops of the bags being flattened and`aligned in a common plane, a pair of heat sealing members adapted toreleasably clamp upon attened tops of the bags, a carriage serving tomount said members, means for tracking said Carra-ige for movement ofthe same in a direction parallelto said plane and tc the path ofmovement ofv the bags through the machine, and means including a membercontacted by the tops of the bags during their movement through themachine for actuating said members to clamp and release the tops of thebags.-

5. In a machine for heat sealing bags after the insertion of a producttherein, means for conveying the separate bags along a predeterminedpath through the machine with` the tops of the bags being flattenedandextending upwardly in a common` plane, a pair of heat sealing membersadaptedv to clamp uponopposite sides ofl the flattened tops ofthe bags,a carriage serving to mount saidv members, means serving to track thecarriage for movement of the carriage along a path parallel to the pathof movement of the bags, means serving to yieldably urge the carriagetoward one'limiting position of the same and'in a direction opposite tothe direction of movement ofthe bags through the machine, vmeans adaptedto be energized to position said sealing. members in clamping andgrippingrelationV with the attened tops of a bagwhereby during suchgripping relationfthe carriage and said members are caused to movealongV with the gripped bag, and bag engaging control means forenergizing said actuating means.

6. Amachine as in claim l in which the means serving to operate saidsecond switch is a cam, the cam having a portion serving to retain thesecond switch closedl during returnmovement of the carriage.

7. A' heat sealing machine as in claim 1 in which said motive means is asolenoid mounted upon the. carriage.

8. Amachine as in claim 3 together with switching means for applyinghigh frequency current to said electrodes only while the electrodes gripa bag.

9'. In a machinefor heat sealing bags, conveyor 8; means f'o'r moving abag along a predetermined" path with the open end condition, a carriagemounted for movement along a path parallel to said predetermined path, apair of heat sealing members carried by said movable carriage, meansadapted to be energized for movf ing said members intoclampingengagement withv the flattened end of the bag to lock said carriagev forconjoint movement with the bag as it is acl-- vanced by said conveyormeans, and means for controlling energizat-ion of said last meansA tomaintain such clamping engagementl for apre determinedv period of suchconjoint movement.

10. lIn a machine for heat sealing bags, con'- veyor means for moving abag along a predeterV mined path with the open end of the bag innattened condition, a carriage mounted for movement along a pathparallel to said predetermined path, a pair of heat sealing memberscarried by said carriageV and arranged to' relesably clamp the flattenedend or the bag as it is moved along by said conveyor means, the clampingengagement of said heat sealing members with the ii'attened bag andbeing effective to cause said carriage to move along with the bag,control means operable upon actuation to energize said heat sealingmembers, and means'l responsive to' movement ofsaidv carriage foractuating said control means;

l 1l. In a machine for heat sealing bags, conveyor means for moving av`bag along a predetery mined path with the open end of the bag inflattened condition, a carriage mounted for move-K- ment along a pathparallel to said predeterminedpath, a pair of heat sealing memberscarriedv by said carriage and arranged to releasably clamp-the flattenedend of the bag as it is moved along by said conveyor means,l theclamping engagement of said heat sealing members with the flattenedf bagend being eiectivel to cause said carriageto move along with the bag,control means operable upon actuation to energize said heat sealingmembers, and means carried by said carriage for actuating said controlmeans to energize said heatY sealing means and retain said control meansinactuated position during apredetermined extent of movement ot saidcarriage.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,432,412 Haclrlander Dec. 9,-1947 2,439,918 Auxier et al.Apr. 20, 1948 2,446,523 Welch Aug. 1U, 1948 2,467,879 Billeb Apr. 19,1949 of the bag in flattened

